Clinical Significance. As one of the most common chronic conditions in the United States, chronic rhinosinusitis invokes a direct treatment cost of $3.5-5 billion annually. Its incidence is 146 per 1,000 and increasing (17). Our prior studies have shown that individuals with two copies of the active form of T2R38 have nasal epithelium that defends very effectively against certain bacteria, such as Pseudomonas aeruginosa, and are less likely to develop severe chronic rhinosinusitis requiring surgery, while those with two inactive forms cannot defend themselves as effectively, and are more likely to develop severe chronic rhinosinusitis requiring surgical intervention. Because the treatment of chronic rhinosinusitis involves multiple rounds of antibiotics and often surgical management through functional endoscopic sinus surgery (FESS), this research has significant implications for antibiotic stewardship, surgical morbidity and mortality, and health care expenditures.